فهرست مطالب محمد رضا اتابکی

Today, sewage sludge disposal methods include drying, burning and application in land, but each of these methods has its own vulnerability. Sewage sludge management is difficult not only because of high levels of production, but also because of high concentrations of heavy metals and pathogens. Research has shown that the transfer of sewage sludge to organic fertilizers, including organic fertilizer, is due to its many advantages, including less heavy metals, easy to use with irrigation systems, faster absorption by plants, and increased their growth efficiency etc. which have been very much considered. The purpose of this study was to investigate the properties of sewage sludge and the liquid fertilizer produced from it.

In this study, biological sludge was transformed into liquid fertilizer using a 0.25 molar solution. Characterization of biological sludge and liquid fertilizer by conducting heavy metal concentration tests (Zn, Pb, Cd, Cr, Ni, Fe and Cu), total nitrogen, total phosphorus, soluble potassium, total sodium concentration, electrical conductivity and pH was done.

The results showed that total nitrogen, soluble potassium, heavy metals concentration decreased with increasing of organic matter extraction from sludge whereas, the amount of phosphorus, total sodium content, electrical conductivity and pH increased.

The results of this study showed that the liquid fertilizer produced from sewage sludge due to its characteristics can be used as a soil modifier in agricultural sector.

Heavy metals contamination of soils is one of the main environmental problems. Heavy metals are considered as one most dangerous groups of pollutants because of their toxicity and stability. The biological and ecological importance of heavy metals is due to their characteristics of polluting, their toxicity, persistence and bioaccumulation. The aim of this study was to investigate the spatial distribution of heavy metals in the different north areas of Isfahan.
In the present study, 30 soil samples (0-20 cm depth) were randomly collected and the total concentration of Pb, Cd, Zn and Cu were measured using Perkin Elmer's atomic absorption device. Also, some other soil properties including pH, EC, organic carbon, soil texture and organic matter proportions were measured. The inverse distance weighting (IDW) method was used for interpolation and mapping of the heavy metals concentration.
Findings: The results showed that the average concentrations of Pb, Cd, Zn and Cu in the study area were 47/16, 2/26, 57/35 and 22/31 mg/kg respectively. Also the results of statistical analysis showed that the standard deviations of Pb, Cd, Zn and Cu in the study area were 7.13, 0.51, 5.56 and 2.84 respectively.
The results indicate that the averageconcentrations of Pb and Cd in the soil of study area were higher than the global standard and Cu and Zn were lower than the global standard.

suspended particles has numerous negative effects on human health and plants.it plays an extremely important role in global climate change as well.
In this survey, variations and influence of meteorological parameters on the concentration of PM10 concentrations were studied.
In this study, first, daily, monthly and seasonal concentrations variation of PM10 were investigated. Then, the degree of correlation between PM10 and meteorological parameters were analyzed by Pearson correlation. Also regression model was used to predict PM10 concentration.
Findings: Daily average PM10 concentration during the study period indicates that the highest concentration was in the 22nd August (1077 µg/m3) and the lowest in the 8th march (42 µg/m3). It also shows the monthly average concentration was in August (301/06 µg/m3), While the lowest concentration is accounted November (152/16 µg/m3). Seasonal concentration showed that the highest concentrations are in the summer (272/76 µg/m3). Pearson correlation coefficient analysis shows that particulate matter has a direct correlation with temperature and wind speed, while reverse correlation with precipitation and atmospheric pressure.
Based on the results of Pearson correlation, it was found that rainfall and relative humidity have adverse effects but the temperature and wind speed have a direct impact on the concentrations of PM10. So that the increased rainfall will reduce the concentration of PM10. While the temperature and the wind speed increases the concentration of suspended particles. Also, the coefficient of determination in the regression model Suggests that 13, 25 and 6 percent of PM10 changes in spring, summer and fall are explained by meteorological parameters used in the model. Based on these results we can say that adverse meteorological conditions may lead to increased concentrations of PM10.